Replacement mitral valve

ABSTRACT

A sewing ring ( 12 ) has a diameter commensurate with a diameter of a removed mitral valve. Skirts ( 44, 46 ) of mesh or net material extend downward from the sewing ring and line the walls of an associated vessel ( 58 ). Basal chordae simulating structures ( 34, 36 ) in the form of elongated strips of mesh or netting, rods, or the like extend from the skirt to an underside of each of two valve leaflets ( 14, 16 ). Marginal chordae simulating structures ( 30, 32 ) extend between each leaflet and the basal chordae simulating structure. The sewing ring ( 12 ) is stitched to an open end of a vessel and inner ends of the basal chordae simulating structure are stitched or stapled ( 50, 52 ) to associated papillary musculature ( 54, 56 ). In this manner, the papillary muscles assist in controlling the timing and control of the mitral valve.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to replacement valves for thecirculatory system. It finds particular application in conjunction withmitral valves for human hearts and will be described with particularreference thereto.

[0002] Heretofore, various styles of flow operated check valves havebeen utilized as replacement heart valves. One prior art heart valveincludes a ball and valve seat arrangement which limits blood flow to asingle direction. A cage surrounding the ball and attached to a sewingring around the valve seat limits movement of the ball away from thevalve seat and natural blood flow.

[0003] In another prior design, a tilting or pivotal disk is mounted inthe valve seat. Flow in one direction causes the disk to tiltperpendicular to the seat, allowing blood flow. Pressure in the otherdirection presses the disk valve closed.

[0004] In another mechanical valve, a pair of flexible leaflets closethe opening between the sewing ring. The leaflets are configured to flexin one direction with flow, permitting blood flow in that direction.Pressure in the opposite direction presses the leaflets together into asealing relationship.

[0005] Bioprosthetic valves have also been utilized. For example, anaortic valve from a pig has been mounted in the sewing ring and used asa replacement mitral valve. However, this aortic valve has threeleaflets; whereas, the human mitral valve has two. Further, thecross-section of the leaflets in the bioprosthetic valve is differentfrom those in humans.

[0006] All of these valves work based on pressure differential. However,the human mitral valve operates with muscular assistance. Marginal andbasal chordae extend from a lower surface of each leaflet to thepapillary muscles. This muscle assists in valve operation. After a valvereplacement with any of the above-discussed replacement valves, thepapillary muscle no longer provides this assistance function.

[0007] The present invention overcomes the above-referenced problems andothers.

SUMMARY OF THE INVENTION

[0008] In accordance with one aspect of the present invention, areplacement cardiac valve is provided. The valve includes an annularsewing ring and first and second leaflets closing a region inside of thesewing ring to define a valve. Elongated structures extend from anunderside of each leaflet away from the sewing ring. The elongatedstructures have an attachment region adapted to be attached to apapillary muscle.

[0009] In accordance with another aspect of the present invention, amitral valve is provided. An annular sewing ring defines an opening. Acylindrical mesh construction extends downward from the sewing ring. Apair of leaflets define a valve structure connected across the openingof the sewing ring. A synthetic basal chordae means is connected betweenan outer portion of each leaflet and the cylindrical mesh construction.A synthetic marginal chordae means is connected between each leafletadjacent an inner edge of each leaflet where the leaflets meet and thesynthetic basal chordae means.

[0010] In accordance with another aspect of the present invention, amethod of installing a replacement heart valve which includes a sewingring, valve leaflets, an anchoring skirt attached to the sewing ring,and a plurality of structures which mimic basal and marginal chordaeconnected between the leaflets and the skirt is provided. The methodincludes rolling or folding each skirt portion up towards the sewingring. The sewing ring is positioned in surrounding tubular vascularstructure where the replacement mitral valve is to be installed nomatter the surgical removal procedure. The sewing ring is sewn into thecavity. The leaflets are opened and where the leaflets open, the skirtis unrolled or unfolded along with the chordae mimicking structures.With the leaflets still open, the chordae mimicking stuructures and thesurrounding skirt are attached to papillary musculature.

[0011] One advantage of the present invention is that it mimics thehuman mitral valve more accurately.

[0012] Another advantage of the present invention resides in its ease ofinstallation using conventional surgical techniques.

[0013] Still further advantages of the present invention will becomeapparent to those of ordinary skill in the art upon reading andunderstanding the following detailed description of the preferredembodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The invention may take form in various components andarrangements of components, and in various steps and arrangements ofsteps. The drawings are only for purposes of illustrating a preferredembodiment and are not to be construed as limiting the invention.

[0015]FIG. 1 is a top view of a replacement mitral valve in accordancewith the present invention;

[0016]FIG. 2 is a side view of the valve of FIG. 1;

[0017]FIG. 3 is a perspective view of the valve of FIGS. 1 and 2 withthe artificial chordae structure on one side of the valve removed forsimplicity of illustration;

[0018]FIG. 4 is a perspective view similar to FIG. 3 of an alternateembodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] With reference to FIG. 1, a replacement mitral valve 10 includesa sewing ring 12 around its periphery. The sewing ring is ofconventional construction and of a diameter sized to the patient. Thesewing ring is sewn to the annular vasculature structure surrounding thelocation of the mitral valve to hold the replacement valve in position.A pair of leaflets 14, 16 span the opening defined by the sewing ring.The leaflets can be constructed of biologically compatible syntheticmaterials or of bioprosthetic materials. For example, the leaflets canbe constructed from bovine pericardium.

[0020] With reference to FIGS. 2 and 3, an arc 20 of inner or marginalattachment points is defined adjacent an inner edge adjacent the openingof one of the leaflets 14 and a similar arc of attachment points 22defined on the other leaflet 16. Analogously, outer arcs 24, 26 of outeror basal attachment points are defined on each leaflet. These attachmentpoints are selected substantially in accordance with the attachmentpoints of the marginal and basal chordae of a healthy mitral valve.

[0021] In the illustrated embodiment, a strip of mesh or netting 30, 32is attached along the marginal attachment points and strip of basal meshor netting 34, 36 is attached to the leaflets along the basal attachmentpoints. The marginal mesh or netting sections 30, 32 are attached to thebasal mesh or netting sections 34 at an attachment point 40, 42 aboutmid-way along the basal mesh or netting section 34, 36, respectively.Outer, semi-cylindrical mesh sections 44, 46 extend from the sewing ringalong an interior of the associated vessel.

[0022] Between the attachment point 40, 42 and a terminal end of thebasal mesh or strip sections, a stitch or staple 50, 52 connects thestrip or mesh sections to a papillary muscle 54, 56. In this manner,contractions of the papillary muscle act through the mesh or nettingsections 30, 32, 34, 36 to pull on the leaflets analogous to naturalchordae.

[0023] For installation, the side curtains 46, 48 are rolled up inward,rolling the mesh strips 30, 32, 34, 36 inside. The sewing ring ispositioned in a vessel 58 and stitched into place as is conventional inthe mitral valve replacement surgery. The surgeon then manually opensthe valve 10 and reaches through, unrolling the side curtains. Thesurgeon then reaches through the open valve to stitch or staple thebasal mesh netting and the side curtains to the papillary muscles 54,56. The design is compatible with any of the currently used surgicaltechniques for diseased mitral valves.

[0024] With reference to FIG. 4, the replacement chordae may take theform of rods or single fibers 60. As yet another alternative,bioprosthetic chordae can be utilized.

[0025] The invention has been described with reference to the preferredembodiment. Obviously, modifications and alterations will occur toothers upon reading and understanding the preceding detaileddescription. It is intended that the invention be construed as includingall such modifications and alterations insofar as they come within thescope of the appended claims or the equivalents thereof.

1. A replacement cardiac valve comprising: an annular sewing ring; firstand second leaflets mounted coplanar inside the sewing ring to define avalve which is planar in a closed position; a plurality of elongatedstructures connected with an underside of each leaflet at a plurality ofdistributed points between an opening edge away from the sewing ring andthe sewing ring, the elongated structures having an attachment regionadapted to be attached to a papillary muscle to enable the papillarymuscle to flex the leaflets open.
 2. The valve as set forth in claim 3wherein the plurality of elongated structures include: a first elongatedstructure extending between the underside of each leaflet and theattachment region; and a second elongated structure extending from theunderside of each leaflet and connecting with the first elongatedstructure.
 3. A replacement cardiac valve comprising: an annular sewingring; leaflets closing a region inside the sewing ring to define avalve; a plurality of elongated structures extending from an undersideof each leaflet away from the sewing ring and having an attachmentregion adapted to be attached to a papillary muscle, the elongatedstructures being made of at least one of: mesh, netting, rods, strings,and fibers
 4. The valve as set forth in claim 2 wherein the secondelongated structures are connected to the leaflets along an arc adjacentan inner edge of each leaflet at which the leaflets meet.
 5. The valveas set forth in claim 4 wherein the first elongated structures areconnected to each leaflet in an arc between the inner elongatedstructure and the sewing ring.
 6. A replacement cardiac valve including:an annular sewing ring; first and second leaflets closing a regioninside the sewing ring to define a valve; a first elongated structureextending from an underside of each leaflet away from the sewing ringand having an attachment region adapted to be attached to a papillarymuscle; a second elongated structure extending from the underside ofeach leaflet and connecting with the first elongated structure; and apair of semi-cylindrical mesh curtains extending downward from thesewing ring.
 7. The valve as set forth in claim 6 wherein the firstelongated structures are connected with the mesh curtains.
 8. Areplacement cardiac valve including: an annular sewing ring; first andsecond leaflets closing a region inside the sewing ring to define avalve; a first elongated structure extending from an underside of eachleaflet away from the sewing ring and having an attachment regionadapted to be attached to a papillary muscle; a mesh structure extendingdownward from the sewing ring.
 9. The valve as set forth in claim 8wherein the first elongated structure is connected to the meshstructure.
 10. The valve as set forth in claim 9 further including: asecond elongated structure connected between the first elongatedstructure at a point mid-way between the leaflet and the connection ofthe first elongated structure with the mesh structure, the secondelongated structure further being connected with a corresponding leafletadjacent an inner edge of the leaflet where the leaflets meet in aclosed configuration.
 11. A mitral valve comprising: an annular sewingring which defines an opening; a cylindrical mesh construction extendingdownward from the sewing ring; a pair of leaflets defining a valvestructure connected across the opening of the sewing ring; a syntheticbasal chordae means connected between an outer portion of each leafletand the cylindrical mesh construction; a synthetic marginal chordaemeans connected between each leaflet adjacent an inner edge of eachleaflet where the leaflets meet and the synthetic basal chordae means.12. The mitral valve as set forth in claim 11 wherein the cylindricalmesh construction includes a pair of semi-cylindrical sections.
 13. Themitral valve as set forth in claim 11 wherein the synthetic basal andmarginal chordae means include one of: mesh, netting, rods, strings,fibers, and biocompatible chords.
 14. A method of installing areplacement heart valve which includes a sewing ring, valve leaflets, ananchoring skirt attached to the sewing ring, and a plurality ofstructures which mimic basal and marginal chordae connected between theleaflets and the skirt, the method comprising: rolling or folding eachskirt portion up toward the sewing ring; positioning the sewing ring ina surrounding tubular vessel structure where the replacement mitralvalve is to be installed; sewing the sewing ring into the surroundingvessel structure; opening the leaflets; with the leaflets open,unrolling or unfolding the skirt along with the chordae mimickingstructures; with the leaflets still open, attaching the chordaemimicking structures and the surrounding skirt to papillary musculature.